ya i 98 24 valve and it giving me hard time starting if i leave the truck sitting for long period(over night) it wont start and if i let the lift pump cycle through it will start up and sputter for like second or two then its fine .like there is air in the lines. I have looked at the fuel lines lines and cant find anything but the weird thing is if i leave the truck part on hill with front end down hill it starts right up but if the front end is up hill has problem i have taken it to local shop and they said it might be injection pump but thats acouple months old and i dont believe it is that. i been lookin for answers with people with simialer problems and i think it could be the return lines ? could that be it? oh ya does anybody know if the fass comes with new return lines also thanks

 

Look closely where the fuel heater wires go into the fuel filter canister. The oring around the black plastic part will go bad and allow air to slowly leak into the system. Your overnight problem can be caused by this. As far as the uphil/downhill thing, I think someone had solved that by replacing the checkvalve where the return line comes off of the ip. I replaced mine, it wasn't expensive and it's easy to do.